Antibody Purification Services:
While antiserum can be used directly in assays, specificity is often a problem because the serum contains antibodies against non-specific proteins. For maximum specificity and accuracy in assays, we recommend affinity-purifying serum against the antigen to isolate antibodies against the antigen.

Affinity Purification:
Affinity purification permits isolation of antibodies against the immunizing antigen, thereby eliminating cross-reactivity that would be present in unpurified serum.

To achieve this specificity, pure antigen (typically peptide) is covalently coupled to an affinity column. Serum is then passed through the column, thereby binding antigen-specific antibodies and allowing non-specific antibodies to pass through.

As a result, Monospecific antibodies, which have homogeneity and antigen-binding specificity approaching monoclonal antibodies, can be quickly isolated from a complex mixture of polyclonal antibodies, providing significant cost and time-savings in comparison to monoclonal projects.

Affinity purification of 25 ml of serum is the most popular option and will typically provide 2-3 mg of peptide-specific antibody. For applications requiring larger volumes of purified antibodies, Pacific Immunology® also offers affinity purification of 200 ml of serum using a larger column.

With either purification option, the affinity column is included so that additional purifications can be run as needed. Most columns can be reused multiple times if stored at 4°C.

IgG Purification:
IgG purification provides an efficient method to separate immunoglobulin (antibodies) from other proteins and molecules in the serum mixture, thereby reducing some background in assays. Protein G, which has a natural affinity for the constant region of the antibody’s heavy chain, is typically used to purify immunoglobulin from rabbit and goat/sheep serum. However, please note that this will not provide specificity to the immunizing antigen and so affinity purification is the preferred technique for most applications.

IgG Purification – 25 ml serum: $295.00

IgY Purification:
With custom chicken antibodies, IgY (an avian version of IgG) is collected from the egg yolk. Unfortunately, the yolk cannot be used directly in assays, so IgY Purification is required if an affinity purification isn’t being run. Because of the different structure of the IgY molecule, Protein L is typically used for IgY purifications.